The development of the welding procedures and fatigue of butt-welded structures of aluminium-AA5383

Comparison of two different nozzles for laser beam welding of AA5083 aluminium alloy

“…Coaxial nozzle 45-120 −2/+2 40-100 3-9 Two-pipe nozzle 80-120 −2/+2 60-100 [3][4][5][6][7][8][9] fied that the depth-of-focus produced were very similar and that the resulting minimum spot size was 0.3-0.4 mm in both cases [1]. Helium was used as shielding gas.…”

“…Conventional processes for welding aluminium alloys in the industry are arc welding and resistance welding [3]. Recent progresses in laser welding make this technology particularly advantageous because of its high speed, flexibility and low heat input that induces smaller distortions of welded assemblies.…”

Microstructural changes accompanying repair welding in 5xxx aluminium alloys and their effect on the mechanical properties

“…Surface maps and chemical analysis performed with EDAX-SEM (Figs. 8(a) and (b)), showed that these intermetallics were either Al 6 (MnFe) or Al 6 Mn and AI 3 Fe [1] and were present in the as received parent metal with sizes ranging between 10 and 50 lm. In the weld due to the high temperatures and cooling rates involved in the process finer intermetallics sizes were observed (1-5 lm - Fig.…”

“…As the use of aluminium expands in the ship building sector, a great deal of research is been carried out mainly focusing on the fatigue properties and the long-term performance of the welded junctions. Series of fatigue tests for various loads and cycles are conducted so as to define a safety service limit for welded and especially repair welded structures [1][2][3][4][5]. Nevertheless, few papers examine the microstructural changes that accompany the failure of the junction and are introduced during the welding procedure [6,7].…”

Effect of deep sub-zero treatment on mechanical properties of AA5XXX aluminum plates adjoined by MIG welding technique

“…Owing to the demanding nature of the service conditions and environments in which marine vessels operate, welded components and structures are susceptible to high level of loads, which may cause micro-structural degrade and nal catastrophic failure. As a necessity of using tremendous amount of aluminum alloys in ship construction industry, a great deal of research has been carried out focusing on the longterm performance of the welded joints [15][16][17]. There are only a few papers examining the microstructural changes that result in the failure of the joint which is mostly introduced during the process of welding [18].…”